Here's a few that are sports-related...
* A football or soccer game that is cancelled after the game has started. Lightning, tornado or a riot... are these the only reasons? These sports play in rain or snow.
* A basketball game that is cancelled after is has started. A riot (some of those European games... or Ron Artest in Detroit)?
* A MLB game that is forfeited. When was the last one... was it Disco Demolition Night in old Comiskey Park (1979?)?
* A #1 college team (basketball or football) getting defeated by an unranked team (not in the top 25). I know that Wright State University beat Michigan State 53-49 in men's basketball in 1999. Cannot recall any others off the top of my head in b-ball or f-ball.